1/2. Audiovestibular evolution in a patient with multiple sclerosis.multiple sclerosis is characterized by the presence of multiple plaques within the central nervous system, manifesting as remission and exacerbation of neurologic dysfunction over variable time courses. We present the case of a 20-year-old woman. Before treatment, her auditory brain stem response (ABR) test revealed bilateral prolongation. A caloric test showed canal paresis of the right ear and a normal response on the left. A vestibular evoked myogenic potential (VEMP) test displayed an absent response in the right ear and a delayed response in the left. A magnetic resonance imaging (MRI) scan demonstrated multiple diffuse high signal lesions in the hemispheres, brain stem, and cerebellum. Six months after treatment, the demyelinating plaques were shown to have resolved spontaneously on MRI. Recovery of caloric responses was anticipated. Bilateral prolongation of ABRs remained, but the VEMP test disclosed a normal response in the right ear and a delayed response in the left. Accordingly, in addition to MRI, caloric tests and ABR and VEMP tests are useful in monitoring the evolution of audiovestibular function in patients with multiple sclerosis.- - - - - - - - - - ranking = 1keywords = caloric (Clic here for more details about this article) |
2/2. Symptomatic high frequency/acceleration vestibular loss: consideration of a new clinical syndrome of vestibular dysfunction.CONCLUSION: Symptomatic high frequency/acceleration vestibular loss is a distinct clinical entity that can be missed on conventional ENG with caloric testing. Under certain circumstances, symptomatic patients with a high frequency/acceleration vestibular loss should undergo an MSSC study for confirmation, if required. OBJECTIVE: To document that normal electronystagmography (ENG) with conventional bithermal caloric testing is inadequate for diagnosing clinically significant high frequency/acceleration vestibular loss. MATERIAL AND methods: patients with clinical symptoms and signs of persistent peripheral vestibular dysfunction despite normal conventional bithermal caloric testing on ENG underwent high frequency/acceleration horizontal magnetic scleral search coil (MSSC) eye movement studies. The clinical findings and results from audiometric tests, conventional ENG with bithermal caloric tests and MSSC tests were reviewed. RESULTS: Eleven patients were identified as having an abnormal MSSC study, indicating a high frequency/acceleration vestibular loss consistent with their clinical history despite normal or equivocal bithermal caloric responses on conventional ENG. Although valuable, ENG caloric testing evaluates lateral semicircular canal function and should be considered a non-physiological test primarily of low frequency vestibular function. High frequency/acceleration head thrust testing clinically detected a "high frequency/acceleration vestibular loss" in 8/11(72.7%) cases.- - - - - - - - - - ranking = 2keywords = caloric (Clic here for more details about this article) |